If you want to copy across a version of your production site exactly as it is, select Overwrite content even when staging version is more recent. If you made recent changes in your staging environment, selecting this will overwrite those changes.

Click OK.

Click Settings under the site you want to use.

Click Staging in the top green menu bar.

Click Sync Sites in the top right corner of your screen.

Select Pull production to staging.

Note: If you want to copy across a version of your production site exactly as it is, select Overwrite content even when staging version is more recent. If you made recent changes in your staging environment, selecting this will overwrite those changes.